pretty sedge

softstem bulrush

Sedges are superficially similar to grasses and rushes, and differentiating the three can be difficult. The rule of thumb is that sedges have edges, rushes are round, and grasses have nodes down to the ground. This refers to the culms, ie the flowering and seed bearing stems. In sedges they are triangular, in rushes they are round, and in grasses they have nodes (joint-like structures). However these are just guidelines and there are exceptions. The main distinction between sedges and true grasses is that the former will always be a perennial, whereas the latter can also be an annual. From a cultivation stand point, many sedges are better adapted than grasses to wet and/or shaded environments. They tend to be highly ornamental, can vary widly in form and visual characteristics, and include many evergreen species.